Topping Centaurus R2R DAC Review

[JSmith]

Measurements aren't done with ears as ears/brains are unreliable.

Actually one can only conduct an AB or ABX test using their ears...


JSmith

 

[antcollinet]

When musicians tune their instruments by ear, is it unreliable?

They are not trying to detect noise and distortion down at -80dB or lower (or even -40dB or lower) when they are tuning an instrument.

 

[VientoB]

Actually one can only conduct an AB or ABX test using their ears...


JSmith

ABX tests aren't measurements.Thats just statistical analysis of listening tests.

 

[VientoB]

When musicians tune their instruments by ear, is it unreliable?

No because if they are experienced at tuning by ear they will get them tuned accurate enough. If you measured how accurate they were they will not be as accurate as doing it with the best measuring equipment I can guarantee you.

 

[MAB]

ABX tests aren't measurements.Thats just statistical analysis of listening tests.

It's a measurement of a subject's or group's response. Statistics are often used in evaluating responses.

 

[VientoB]

It's a measurement of a subject's or group's response. Statistics are often used in evaluating responses.

Yes it is a statistical measurement.

 

[Jimster480]

"The earliest non-oversampling CD players were R2R and critics called them bright, shrill, gritty, glassy, shouty,"
You mean the earliest Japanese NON-oversampling DACs? Perhaps it is a fair accusation. But the early Philips (TDA1540) and its TDA1541 successor certainly could not be accused of such traits. If anything, they sounded a bit rounded and veiled in comparison. But even those Japanese R2R DACs had come along way only half a decade later, and they sounded on the whole quite respectable. Technology has come a long way since, and as evidenced by this review, R2R implementations are arguably the best they have ever been...

Yet now that R2R is the "best they have ever been" and the performance is still greatly under DS.... I think it is safe to put the discussion to rest.

"Measurements, schmeasurements—do yourself a favor and try this BorderPatrol DAC. Yes, it’s a Redbook-only converter, and yes, it sports NOS chips. And so what? Chances are, you’ve never heard digital like this, and certainly at nowhere near its price. There is no oversampling, no up-sampling, and no filtering. This is “do no harm,” taken seriously. Add a choke-input and tube rectified power supply, and forget David, here you have an Audio Goliath. Clear, open, transparent, sound flows forth like sweet water poured from the hands of friendly, loving gods. According to the musicians who made it, this was how your music was supposed to sound"

Wow! That's a whole lot of Audiophool's Drivel, and I have read quite a lot of it before... And again, R2R is not a synonym for "NOS".

Not sure why so many seem to confuse these two things. Just because it is R2R doesn't mean that it cannot oversample....

When musicians tune their instruments by ear, is it unreliable?

It definitely can be. I have watched my wife tune her violin many times. She uses an app with a phone.
You tune by listening to very specific flat frequency notes. So A B C, etc
Just like A = 440Hz, D = 293.7Hz, G = 196Hz, E= 659.36Hz/660Hz These are all for a Violin. However it is like listening to a sine wave, they do not play songs and then tune based on a song.

I suspect the earliest R2R dacs had resistor mismatches making them sound non-linear ie bright shrill etc. as mentioned. Nowadays R2R implementation have taken care of the resistor mismatches ie the resistors are matched towards a certain tolerance thereby improving the sound.

Except they are just still not as good as the Delta-Sigma method. The math for Delta-Sigma can produce a flawless sound without the need for such precise resistor tolerances.
I always thought how R2R worked was "cool" but in practice it is like a carburetor vs fuel injection (or even more modern direct injection). The precision with a modern day solution is just much better and doesn't vary on manufacturing tolerances.

"My speakers sure seem to fluctuate quite a lot between summer and winter. 30+ degrees centigrade in summer, and the bass seems much fuller, sound warmer. But I don't think that is a temperature bias in my head because it is indeed hotter!"

Air Temperature has an observable and well attested effect in Sound Reproduction. Listening to Music through Warm Air is invariably more pleasurable, all other variables withstanding...

That is interesting, I never thought about the affect of air temperatures on sound. Is there a writeup for this? An optimal temp?

 

[Jimster480]

It's a measurement of a subject's or group's response. Statistics are often used in evaluating responses.

The problem I have seen with most ABX testing is that it is done in a very informal way. In music distortion can hide easily, and you have to know what to listen to in a track. Otherwise you could gloss completely over all distortion upto 1%+ THD in some scenarios.
This is why it is important to have something that measures well as a "baseline" and then you can try to hear the differences in the inferior product.
When listening for things to "be better" in a better performing product, you have to listen to the peaks at the higher frequencies which are the most likely to have distortion.
Since even a product with low SINAD should generally perform well in lower frequencies, unless it is an Amp with a poor current delivery topology.... which I believe was the case with most class D amps from some years ago.

When people just "listen to music" and try to hear differences without separating the sounds in the music; they start hallucinating and coming up with all sorts of words to describe what the are hearing.... most of which is just nonsense because your audio memory isn't long enough to be able to put together a thought like that.
The other thing is that most of the time you read about ABX testing; they don't play a specific segment of a song over and over again to try to listen for differences.... just "music" is played and people are asked to guess.
When telling differences in real audio performance; you should only listen to 30 seconds at max and try to choose 7-14 seconds out of that to try to evaluate if you THINK you hear a difference. Then Narrow it down to 7 actual seconds and then 5 or so seconds so you can try to determine if there is a difference. Sometimes you will find that there is no difference even if you THOUGHT you heard one. This is why it is important to have a methodology for testing.... most people buy new gear and just replace their old gear while never doing an ABX test at all... some never do any test at all.... some do crazy sighted bias tests and swear their "new gear" sounds great.... others buy poor quality products and then say that "you have to burn it in for 80 hours".... that process is to train your mind to listen to the worse quality audio, because it won't do anything for the electronics.

 

[VientoB]

"My speakers sure seem to fluctuate quite a lot between summer and winter. 30+ degrees centigrade in summer, and the bass seems much fuller, sound warmer. But I don't think that is a temperature bias in my head because it is indeed hotter!"

Air Temperature has an observable and well attested effect in Sound Reproduction. Listening to Music through Warm Air is invariably more pleasurable, all other variables withstanding...

Air pressure affects the speed sound travels at. So on a low pressure day you might be at 970 mb and high pressure perhaps 1030 mb. That will probably affect the sound of your system. Will probably sound better on high pressure days.

 

[raif71]

Except they are just still not as good as the Delta-Sigma method. The math for Delta-Sigma can produce a flawless sound without the need for such precise resistor tolerances.
I always thought how R2R worked was "cool" but in practice it is like a carburetor vs fuel injection (or even more modern direct injection). The precision with a modern day solution is just much better and doesn't vary on manufacturing tolerances.

Agree to disagree. Who's to say which is better sounding DS or R2R in this subjective hobby? Even now there are still people preferring vinyl over CDs

 

[VientoB]

Agree to disagree. Who's to say which is better sounding DS or R2R in this subjective hobby? Even now there are still people preferring vinyl over CDs

I think the main thing people are saying is they should both sound the same. Maybe a slight treble roll-off with the R2R if there's no oversampling.

 

[antcollinet]

Agree to disagree. Who's to say which is better sounding DS or R2R in this subjective hobby? Even now there are still people preferring vinyl over CDs

Better sounding? Sure, that can be a preference.


However, since this hobby has always been about higher accuracy leading to transparency (low distortion, low noise, flat frequency response) it is easy to say what is more accurate. Higher Fi if you like.

 

[raif71]

I think the main thing people are saying is they should both sound the same. Maybe a slight treble roll-off with the R2R if there's no oversampling.

My bad...I was responding to the poster when he mentioned that DS produce flawless sound.

 

[Sokel]

Yet now that R2R is the "best they have ever been" and the performance is still greatly under DS.... I think it is safe to put the discussion to rest.

To be correct no, that's not the best measuring one, mother Holo who gave the modules to this one is with its Holo May at 118dB SINAD.
And not far at all from the best DS ones.

 

[MatrixS2000]

When musicians tune their instruments by ear, is it unreliable?

Yes, that is why tools like this were created:

 

[Sokel]

Yes, that is why tools like this were created:

That's rocket science.
Thousands years old this tells the story:

Crossrelation and false relation is the fun way to do it.

 

[MatrixS2000]

Thousands years old this tells the story:

So we have known for thousands of years that ears are not trustworthy, yet in 2025 some still believe ears are fine measurement devices.

 

[srrxr71]

Air pressure affects the speed sound travels at. So on a low pressure day you might be at 970 mb and high pressure perhaps 1030 mb. That will probably affect the sound of your system. Will probably sound better on high pressure days.

I haven’t heard about temperature per se but yes pressure and humidity influence the speed of sound.

One of my systems is in a bedroom with an attached bath. Sometimes I just turn the shower on to raise the humidity but I can’t really hear a difference.

There are some professional sound reinforcement professionals who account for humidity, temp and pressure. Read it in some concert sound article.

 

[VientoB]

Humidity has a small but measurable affect on the speed of sound (0.1% to 0.6%)

The H2O molecules are lighter then the O2 and N2 they displace, so sound travels slightly faster in humid air than in dry air.

Also makes it harder to breathe in humid air as there is slightly less oxygen molecules in a given volume.

 

[unpluggged]

The H2O molecules are lighter then the O2 and N2 they displace

If they are lighter, how then they are able to displace them? (And even if so, how a less dense gas medium can have higher speed of sound?) Relative air humidity is a measure of partial pressure of water vapor in the air; the speed of sound is a function of total air pressure, which already accounts for all the partial pressure components from all gases that compose the air, including dihydrogen monoxide.